Documents leaked by CIA whistleblower Edward Snowden detailed how spooks told how they could monitor map and social network apps

Spies were able to tap into the Angry Birds smartphone app to snoop on Britons, it was revealed last night.

Documents leaked by CIA whistleblower Edward Snowden detailed how British spooks at GCHQ in Cheltenham showed a pilot project to the National Security Agency in the US in which they could monitor map and social network apps.

Codenamed "Squeaky Dolphin", the technology collected personal data from millions of videos and had the capacity to spy on Facebook and Twitter.

Both British and American spies also plotted ways to gather info from Angry Birds and other smartphone apps, it was claimed.

A spokesman for GCHQ last night refused to confirm or deny the claims, adding: "Our work is carried out in accordance with the law."

It the latest leak to come from the cache of documents stolen by American Snowden, who has just had his one-year visa to live in Russia extended.

Getty

Whistle blower: Edward Snowden

The 30-year-old CIA whistle blower fled the US last May after exposing the NSA’s PRISM program.

It gave officials access to data held by nine of the world’s top internet companies, including Google, Facebook, Microsoft and Skype.

One of the documents leaked by Snowden to the Washington Post, dated 9 January, 2013, says that in the previous 30 days over 181 million pieces of information had been processed by the NSA and GCHQ, under a specially devised programme called MUSCULAR.

Last night GCHQ refused to confirm or deny the existence of the Squeaky Dolphin program.

In a statement, a spokesperson emphasised the agency operated within the law.

It read: “All of GCHQ's work is carried out in accordance with a strict legal and policy framework which ensure[s] that our activities are authorised, necessary and proportionate, and that there is rigorous oversight, including from the Secretary of State, the Interception and Intelligence Services Commissioners and the Parliamentary Intelligence and Security Committee. All of our operational processes rigorously support this position.”

A spokesperson for the NSA said the US agency is not interested in “the communications of people who are not valid foreign intelligence targets.”

British intelligence agencies along with their U.S counterparts also plotted ways to gather data from Angry Birds and other smartphone apps that leak users' personal information onto global networks.

Snowden's documents claimed both countries had tried to exploit increasing volumes of personal data that spill onto networks from new generations of mobile phone technology.

Among these new intelligence tools were "leaky" apps on smartphones that could disclose users' locations, age, gender and other personal information.

The U.S. and British agencies were working together on ways to collect and store data from smartphone apps by 2007.